City report. City of London. Read 20 September to 27 October 2026.
More than half of City of London businesses that run their own email publish no enforced DMARC policy.
We read 1,702 office businesses in City of London. 1,579 of them run email on their own domain, and 55% of those publish no DMARC policy, or one set to monitor only. Counts only, and no business is named.
| What we counted | City of London |
|---|---|
| Office businesses read | 1,702 |
| Run email on their own domain | 1,579 |
| Publish no enforced DMARC policy | 55% |
| Read between | 20 Sep and 27 Oct 2026 |
No enforced DMARC policy means no DMARC record was published for the domain, or the record's policy is p=none. A record at p=quarantine or p=reject counts as enforced.
How this was counted
Every figure on this page comes from what a business publishes about itself, read on the dates shown.
- Which businesses. Office businesses with a website of their own, drawn from the Overture Maps places inside the boundary of City of London and the Companies House register.
- What was read. The domain's public DNS records, the certificate it presents in a TLS handshake, its home page and a few of its own public pages, every request listed in the method. No port was scanned, no private file was asked for, and nothing was logged into.
- Own email. A business runs its own email if its domain publishes MX records that are not a free webmail service.
- The DMARC count. One TXT query for _dmarc on each of those domains. No record, or p=none, counts as not enforced.
- Dates and receipts. Every read is dated. The record text is kept, and a receipt is made for each one.
If you run an IT support firm in City of London
Most of those businesses can be fixed with one TXT record. That is a finding you can put in the first email, dated, with the fix attached.
A Pack for City of London is at least 100 of those businesses within about ten miles of your office, ranked, with the record, the fix, a call sheet for every one, and first emails for those you can email. A business in your pack goes to no other firm for 30 days after your pack is made, and we never sell areas.
Other cities
| City | No enforced DMARC | Read | Report |
|---|---|---|---|
| Leeds | 77% | Read 20 Sep to 29 Oct 2026 | Report |
| Bradford | 81% | Read 20 Sep to 29 Oct 2026 | Report |
| Wakefield | 78% | Read 23 Sep to 27 Oct 2026 | Report |
| Manchester | 74% | Read 20 Sep to 30 Oct 2026 | Report |
| Sheffield | 79% | Read 23 Sep to 30 Oct 2026 | Report |
| York | 79% | Read 23 Sep to 25 Oct 2026 | Report |
| Birmingham | 78% | Read 20 Sep to 27 Oct 2026 | Report |
| Bristol | 74% | Read 20 Sep to 12 Oct 2026 | Report |
| Reading | 70% | Read 20 Sep to 27 Oct 2026 | Report |
| Milton Keynes | 74% | Read 20 Sep to 23 Oct 2026 | Report |
| Westminster | 69% | Read 20 Sep to 27 Oct 2026 | Report |
| Islington | 70% | Read 20 Sep to 27 Oct 2026 | Report |
| Hackney | 77% | Read 20 Sep to 27 Oct 2026 | Report |
| Camden | 71% | Read 20 Sep to 27 Oct 2026 | Report |
| Tower Hamlets | 71% | Read 20 Sep to 26 Oct 2026 | Report |
| Barnet | 81% | Read 20 Sep to 24 Oct 2026 | Report |
| Newham | 80% | Read 20 Sep to 26 Oct 2026 | Report |
| Harrow | 82% | Read 20 Sep to 18 Oct 2026 | Report |
| Hounslow | 77% | Read 20 Sep to 14 Oct 2026 | Report |
| Redbridge | 85% | Read 20 Sep to 26 Oct 2026 | Report |
| Croydon | 78% | Read 20 Sep to 26 Oct 2026 | Report |
| Nottingham | 72% | Read 20 Sep to 19 Oct 2026 | Report |
| Southwark | 68% | Read 20 Sep to 21 Oct 2026 | Report |
| Leicester | 77% | Read 20 Sep to 21 Oct 2026 | Report |
| Hillingdon | 76% | Read 20 Sep to 27 Oct 2026 | Report |
Reports are republished when a city is read again. All city reports. To cite this report, link to this page and give the read dates.